“I don't know if it's just in our culture, or whether it's a boy thing, that they find it very hard to pick up a book or go to a film if a girl is the central character,” Child tells BBC News.

“I don't know where that comes from but it worries me because it makes it harder for girls to be equal,” she adds.

The author has just published the last Ruby Redfort book. Ruby began as a character in her Clarice Bean series, but Child decided to give her her own spin-off series after being inundated with requests from young girls.

“You could quite easily change Ruby's name to a boy's name and just changing a few details in the book and it would work just the same,” she says.

Boys ‘find it very hard’ to read a book starring a girl hero, says the new Children's Laureate